Tuesday, November 10, 2015

Muscles ( ESSAY )

Your muscle cells is one of the places that you can find insatiable longing, forbidden love and tragic separation, and those love story is played out by a nice pretty pair of protein strands called actin and myosin. These couples love story is the reason that you can move, dance, or even stand up. It makes ALL of your motions possible, not just the voluntary stuff, but also the involuntary, like your heart pumping and your stomach digesting the food that you just gulp down. So someone better give them a movie contract cause these story is very important. The amazing thing about your muscle tissue is that they turn potential energy into mechanical energy or movement, simply by doing two things : contracting and relaxing. I hope you remember the types of muscle tissue in our bodies :
  • Smooth
  • Cardiac
  • Skeletal
If you don't remember check out my post on this three types of muscle tissue. But right now, I'll only talk about your 640 skeletal muscles. These are mostly voluntary, meaning that you can control what they do, you have to command them to move them, unlike the other two type of muscle tissue which is involuntary. Most of your skeletal muscle tissue are attached to your bone and create movement by pulling or pushing the bone this way and that. Each one of your skeletal muscles is technically its own organ, because they contain connective tissue, blood vessels, and nerve fibers. Add one more to the list of organs that you never know about. And because your muscles are voracious energy hogs, each one is rigged up with its own personal nerve to stimulate contraction, and its own artery and vein to keep it well fed with all the blood, oxygen, and proteins they would need to operate. But to understand those operations, we need the "anatomy of the skeleton badge" under our "anatomy and physiology belt", so let's move on partner. Basically, a skeletal muscle is constructed like a really sturdy piece of rope. It contains fibers, layers and layers deep. Thousands of tiny parallel threads called myofibrils squish together to form muscle fibers, which are your actual muscle cells, which is no different from any other cell. It contains mitochondria, multiple nuclei, and a cellular membrane called a sarcolemma. Those muscle fibers then form larger, string-like bundles called fascicles, which combine to form the larger rope-like muscle organ. Overall, this bundles-within-bundles configuration makes muscle tissue fairly sturdy. But considering how much abuse your muscles take when you do something, it's no surprise that they need a little help. That's why every muscle contains a few different kinds of supportive sheaths of connective tissue, the protective reinforcements to keep that bulging muscle from bursting. Well the anatomy part of the story is complete, now we'll approach the "how" part of the story. But, there are rules before we go on :
  1. Proteins like to change shape when stuff binds to them
  2. Changing shapes can allow proteins to bind or unbind with other stuff
So keep those rules in mind and you should be okay. Now let's go back to those myofibrils that forms kinda like the base of the muscle cell. It is divided lengthwise into segments called sarcomeres, which contain two even tinier strands of protein -- two different kind of myofilaments called actin and myosin, the lovebirds. A sarcomere contains both thin filaments, made up mostly of two light and twisty actin strands, and thick filaments, composed of thicker, lumpy-looking myosin strands. Each sarcomere is separated by what's known as a Z line at either end, which is just a border formed by alternating thin filaments in a kind of zig zag pattern. When you are at rest, your actin and myosin strands are not touching, but would really, really like to touch one another. Specifically, those club-headed myosin wants to get up-close-and-personal with the actin strand. But just like a good human love story, this love story also have some obstacles that wanted to keep them separated. And this "obstacle" is a protein called tropomyosin and troponin. But luckily these bodyguards can be bought off by Adenosine Triphosphate, or better known as ATP, and some calcium. ATP is like our bodies main body of currency that is welcomed in all part of your body, not like different country have different currencies. ATP contains chemical energy, and your muscles are all about converting chemical energy to motion, so they are always hungry for more ATP. Say I want to move my arm. My brain then sends action potentials along the motor neuron until it synapses with a muscle cell in my arm. Then the motor neuron releases acetylcholine into the synapse, the channels open up, and then create a rush of sodium into the cell as a graded potential, which, if it's strong enough, causes nearby voltage-gated sodium channels to open. So that action potential zips along a muscle cell's membrane, the sarcolemma, which has lots of tubes that run deep inside the cell, which are called T-Tubules. When the action potential travels down one of those tubes, it eventually triggers the voltage-sensitive proteins that are linked to those calcium channels on the cells sarcoplasmic reticulum. When those channels are thrown open, the calcium stored inside rushes into the rest of the cell. The protein troponin just loves to bind with calcium, and remember rule #1. So the calcium latches on to the troponin which then pulls on the other bodyguard, the tropomyosin away from the sites on the actin strands that the myosin really wants to get a hand on. But the only myosin heads that can bind to those newly opened sites are the ones that are ready for action. That is, the one that have already grabbed a molecule of ATP that's been floating around, and broken it down into ADP and the leftover phosphate. When a myosin head does that, it changes shape in to an extended position, kinda like a stretched spring, still holding on to the ADP and phosphate, and still storing the energy that was released when they were broken apart. When that energy was released, the myosin finally "kiss" her beloved boy. So after all that, the myosin finally binds with the actin strands and what a beautiful scene. When they bind, the myosin tugs and pulls on the muscle fibers and that is what makes your muscles stretched and contracts. Now, with it's energy spend, that little head has no use for the ADP and the phosphate. So they un-bind with it, because remember rule number 2, that when proteins changes shape it encourages the protein to bind or unbind with stuff. That created a slight change in the myosin strand, which lets a fresh ATP come and bind with it which created another change, but this time it is what makes the myosin releases on the actin and fall back to its resting stage, contracting the muscle in it's wake. But fear not! This epic is not about to end. This one is very similar to most of your body's processes, it forms a cycle. When it go back to its resting stage, it again turns those ATP into ADP and a leftover phosphate, making it move into the stretched position again, and yes the cycle continues.
Your 640 skeletal muscle comes in different shape and sizes, from the longest (the Sartorius in your upper thigh) to the biggest (the gluteus maximus in your butt), to the tiniest (the stapedius in your middle ear). These organs are capable of a whole range of power and duration, as well as surprising and delicate subtlety. The same muscle that you would use to pluck an eyebrow growing in the wrong place, or catch a mosquito, or hug a baby; those same muscle could be use to crush cans, punch hole through walls like an angry Mama Hulk when her Baby Hulk are being teased by an Evil Brother Hulk, and do push-ups. How can that be possible? Well stick around to find out.
Now when you look at how the muscular system moves, you got to keep two things in mind:
  1. Muscles never push. They always pull
  2. Whatever one muscle does, another muscle can undo.
Wait. How can muscles not able to push? Let's remember that skeletal muscles, well most of them, extends across the joint over to connect at least two bones together. When a muscle contracts, the bone that moves is called the muscle's insertion point. And the muscle brings the insertion point closer to the bone that doesn't move, or at least moves less, and that is called the muscle's origin. And that movement is always a pull, always a muscle tugging on the insertion point to get closer to the origin. And when you think about it, it has to be that way. Muscles cannot, like extends themselves more than their resting point length to push a bone away from the origin after pulling it closer. Every single movement that your skeleton makes uses the very same principal, whether you are doing exercise or writing on a piece of paper, all of your possible movement uses the very same principal, that your muscle are pulling on an insertion point to move it closer to the origin. Keep in mind here that you cannot just say to one of your bone that it is an insertion point. You have to look at the thing that its doing. One bone can be an insertion point when you do this, but it will be the origin when your other muscle counteract what your other muscle has done. I know, its complicated.....
You can generally classify skeletal muscles into four functional groups depending on the movement being performed :
  • Prime Movers
  • Antagonists
  • Synergists
  • Fixators
For example, the muscles that are mainly responsible for a certain movement are called those motion's Prime Movers or agonist muscle. Take an example when you do a series of jumping jacks. You are using those pectorals located in your chest and latissimus dorsi on your back to adduct your arms back down to your sides. Then those muscle are your bodies Prime Movers muscle for adduction. Well referring to the second rule, there would be another muscle to counteract what the Prime Movers do. That's where the Antagonists came. It counteracts what the Prime Movers has done. And one particular muscle could be a Prime Mover when your body are doing this, and can be an Antagonist when your body do the opposite thing. The third functional muscle group that you have is called the Synergists. And like its name it help the prime movers by giving them extra energy, and also to stabilize joints from dislocating from their position, which will be painful, believe me on that one.
Now back to the question of how can you hug a baby in one time and the next minute crush a can. I got two words for you : Motor Units. A motor unit is a group of muscle fibers that all get their signals from the same and single motor neuron. Since all of those fibers listen to only one motor neuron, they act together as one unit. In a big power-generating muscle like your rectus femoris in your quad, each of a thousand or so motor neurons may synapse with, and innervate, with a thousand muscle fibers. Those thousand fibers together form a "large motor unit". And big units are typically found in muscles that perform big, not very delicate movements, like running, kicking, or jumping. But other muscles, the one that control your eyes and fingers, which exert fine motor control may have only a handful of muscle fibers all connected to a single motor neuron. Those relationships are "small motor unit". And when a motor unit, no matter how large or small, responds to an action potential, those fibers quickly contracts and release, in which we call a twitch. The fact is, our muscular movement are pretty smooth. That's because one muscle can produce a variation of smooth forces, called "graded muscle response". And they're generally affected by both the frequency and strength with which they're stimulated. Let's say you want to lift something heavy, like a bucket full of water. Your brain tells your muscle to increase their force, by increasing the frequency with which your motor neurons are firing. And the faster these nerve impulses fire, the stronger each successive twitch gets. In this way, twitches end up adding to each other as they got closer together in time. We call these as temporal summation. At some point though, almost all actin binding sites are exposed, so all of the myosin heads can work through their cycle of ATP and ADP, and the muscle force can't increase anymore, even with faster action potentials and more calcium. It's just that none more myosin are doing nothing, they are all busy, kissing the actin and releasing for a brief short unhappy moment. When all those little twitches blend together until they feel like one mammoth contraction, that's called tetanus. At that point, all human being on planet Earth will hit a ceiling of maximum tension, where there are just no more myosin and actin to bind.     

Monday, November 2, 2015

Joints ( ESSAY )

Joints are the meeting places between two or more bones. And even though it sounds mathematically possible, you actually have more joints than bones, which is weird. In a lot of places, like your hands and feet, each individual bone is part of more than one or two joints. And then what is the job of those joints? To help you move. Body movements happen when muscle contracts across joints, moving one bone toward another. As is often the case in anatomy, we classify joints both by what they do and by what they're made of. Because form follows function, we can't really talk one without talking the other. So the structural classification of your joints is all about what kind of material make up those joints, and it is made of three categories :
  • Fibrous joint  
  • Cartilaginous joint
  • Fluid-Filled or synovial joint
While the functional classification of your joints focuses on how much that particular joint can move, and it is divided into several more groups :
  • Synarthroses; non moving joints
  • Amphiarthroses; partly-moving joints, like shock-absorbers.
  • Diarthroses; fully movable
Fibrous joint connects bones with dense, fibrous, connective tissue and are mostly immovable, so they are mostly classified synarthroses joints.
Cartilaginous joints unite bones using cartilage, they don't move much, and therefore classified as ampiarthroses joint. These come in two types : synchondroses and symphyses.
Synovial joint are freely movable, so they are in the class of diarthroses. Most of your joint fall into this category. Although they do make use of cartilage and fibrous connective tissue to connect bones, they're different in that the bones that they joint are separated by a fluid-filled joint cavity, which is good, because they move a lot, and if all our joints use cartilage or fibrous connective tissue to connect all your bones, a walk down the block would make your joints so hot that it would essentially cook the surrounding tissue and leave your legs smoking like a desperate Looney Tunes character. They also have six special features :
  • band-like ligaments
  • articular cartilage that covers the opposing bone surface
  • a joint cavity
  • synovial fluid lubricant
  • a fibrous joint capsule
  • sensory nerve fibers and blood vessels.
These synovial joints have six different configurations that allow you do all the things that you are capable of doing, like a subtle head nod to a vigorous-whole-body shake :
  • Plane
  • Hinge
  • Condylar
  • Pivot
  • Ball-and-socket
  • Saddle
So that is pretty much the anatomy and physiology of your joints, and Matthew is signing off.

Friday, October 30, 2015

The Skeletal System ( ESSAY )

Though your bones look all dry and austere, don't be fooled, they are actually alive. Bones are considered organs themselves because they contain more than one type of tissue. They are actually as dynamic as any of your organs is, and they are constantly repairing and you basically get a brand new skeleton in 7 to 10 years. They're job is way more than just providing you with support but also to :
  • produce blood cells
  • store energy as fat
  • storage for calcium, phosphate, and other mineral.
  • regulating blood calcium levels
  • producing hormones osteocalcin
  • protects against glucose intolerance and diabetes
So you see, they are basically another one of your organs. An average human body contains 206 bones, ranging in shape and size, from the tiny stapes in your ear, to the huge femur that makes up the entire length of your thigh. Autonomist often divide those bones into 2 categories :
  • axial
  • appendicular
Your axial bones is the bones that are found in your bodies vertical axis, like the skull, well basically all the bones that protect your other organs, ahhhh how heroic.... While your appendicular bones are, well, everything else. From there, your bones are generally classified further by their shape :
  • Long Bones, the classic "dog-bone" style
  • cube shaped Short Bones
  • Flat Bones, the thin bones like the one that cover your brain
  • Irregular Bones, the odd-shaped looking bones, like your vertebrae and pelvis
But despite their variations in size and shape, all bones have a similar internal structure. They all have a smooth, dense external layer of compact, or cortical bone around a porous, honeycomb-looking area of spongy bone. The spongy bone area is where typically you would find your bone marrow, which are found in two colors, red and yellow. The red bone marrow are responsible for creating blood cells, while the yellow bone marrow are the storage for your fat. The arrangements of these bone tissues, though, can be a little different from each other. Like in your flat bone, the spongy bone is in between the cortical bone, while in the long bones, the spongy bones are only found in the tip of the bones, called epiphyses. The basic unit of bones are called osteons. They are cylindrical, weight-bearing structures that run parallel to the bones axis. Look inside one, and you will see them look like tube inside of a tube. Each one of these tubes, called lamellae, is filled with collagen fibers. Now the tube that are in the tube, is filled with nerves and blood vessels. So there you go. A tour of an organ that you have known all your live, without you realizing it to being an organ, like a ninja, eh?

Vision ( ESSAY )

Nearly 70% of all the sensory receptors of your whole body are in the eyes, so it's important to "see" what's going on and what does our eye looks like, right? But the fascinating thing about our eye doesn't end there. In order for you to see, perceive, or recognize anything, nearly half of your entire cerebral cortex has to get involved. Vision is considered the dominant sense of humans, and while we can get along without it, and it can be tricked, what you are about to learn is NOT an illusion.
When I talk about your sense of hearing, I started with the mechanics of sound, and now is not going to be any different. Light is electromagnetic radiation travelling in waves. Remember how the pitch and loudness of a sound is determined by the frequency and amplitude of it's waves? Well, it's similar with light, except that the frequency of a light wave determines the hue, while the amplitude of the light wave determines its brightness. We register short waves at high frequency as bluish color, while long, low frequencies look reddish to us. Meanwhile that red would look dull and muted at low amplitude, while if the amplitude are high it would look bright to us. But the visible light we are able to see are only a tiny chunk of the whole electromagnetic spectrum, ranging from super tiny gamma rays, to super long radio waves. Some of the first things that you will notice if you look at an average pair of eyes, are all the outer things that are created to help protect your eyes from the outside world : the eyebrows, that help keep your sweat away from your eyes; the super-sensitive eyelashes, that trigger reflexive blinking; your eyelids; the tear-producing lacrimal apparatus. The eyeball itself are irregularly spherical, with an adult diameter of about 2.5 centimeters. It's essentially hollow, full of fluids that help keep it's shape, and you can only see about the anterior sixth of the whole ball. The rest of it is safely tucked into a pocket of protective fat, tethered down by six strap-like extrinsic eye muscles, and jammed into the bony orbit of your skull. Your eye's wall is made up of three distinct layers : the fibrous, vascular, and inner layers. The outermost fibrous layer is made of connective tissue. Most of it is that white stuff called the sclera, while the most anterior part is the transparent cornea. The cornea is like the window that lets light in. Going little deeper, there's the posterior choroid, the one that supply all the layers with blood. In the interior, there is also the ciliary body, a ring of muscle tissue that surrounds the lens, but off course the most famous part of the vascular layer is the iris, which is that distinctive colored part of the eye that makes your eye different from anybody else in the world's eye. The pupil is an opening in the iris that let's light in. The opening in the iris is controlled by sphincter muscles, that control how much light gets into your eyes. Light comes in through the cornea and pupil and hits the lens, the transparent, convex disc that focuses that light and projects it onto the retina, which makes up the inner layer at the back of the eyeball. The retina itself has two layers, the outer pigmented layer that helps absorb light so it doesn't scatter around in the eye, and also the inner neural layer.

Wednesday, October 28, 2015

Hearing and Balance ( ESSAY )

Let's start today with several questions.
  • What is sound?
  • How can I hear the sound?
  • How can I walk around without falling on my face?
I'll start off by answering the first question. The basic and short answer to the question of "what is sound" is : 'Sounds create vibrations in the air that beat against the eardrum, which pushes on a series of tiny bones called "auditory ossicles" that move internal fluid against a membrane that triggers tiny hair cells -- which aren't actually hairs -- that stimulate neurons, which in turn send action potentials to the brain, which interpret them as sound.' Short and simple, right? But there is a lot more going on in our ear to just allowing us to hear a beautiful song, it also allows you to stand up, walk, and even dance. Yes, the ear also houses the part of your body that allows you to keep your balance. To better understand how your ears pick up sound, we must first understand how sound actually works. The key to sound transmission is vibration. When I talk, my vocal folds vibrate, creating sound. When I slam this desk I'm writing on, or strum a guitar, those vibrations cause air particles to vibrate too, initiating sound waves that carry the vibrations through the air. To hear a sound, your ear must then pick up that vibration that was travelling through the air, and then send it to your brain that then process it, then, and only then, can you finally hear the sounds. One more thing. You may say, "well they all vibrate, what then makes their sound different?" The difference is in the shape of the sound waves and their frequency. Frequency is the number of waves that pass a certain point at a given time frame. A high-pitched noise is the result of shorter waves moving in and out more quickly, while fewer, slower fluctuations, result in a lower pitch. That is for how high or low the notes are, but for loudness, it depends on the waves' amplitude, or the difference between the high and low pressures created in the air by that sound wave. Now, in order for you to pick up and identify barking or beeping, or any sound at all, the sound waves have to reach the part of the ear where those frequencies and air-pressure fluctuations can register and be understand by the brain. Now let's get to the anatomy of the ear. The ear are divided into three major areas : the external, middle, and inner ear. The external and middle ear are only involved in hearing, but your inner ear is key to both hearing and maintaining your balance, or equilibrium. So the pinna, or auricle, is the part that you can see, and wiggle, or grab, or festoon with an earing. It's made up of elastic cartilage covered in skin, and it's main function is to catch sound waves, and pass them along deeper into the ear. Once a sound is "caught" it is funneled down into the external acoustic meatus, or auditory canal, and toward your middle and inner ear. Sound waves traveling down the auditory canal eventually collide with the tympanic membrane, which you probably better known as the eardrum. This ultra-sensitive, translucent, and slightly cone shaped membrane of connective tissue is the boundary between the external and middle ear. When those sound waves collide with the eardrum, they push it back and forth, making it vibrate so it can pass those vibrations along to the tiny bones located in the middle ear. Now the middle ear, also known as the tympanic cavity, is the relay station between the external and inner ear. It's main job is to amplify things a little bit, so that they are louder when they enter the inner ear. And it needs to amplify those sound waves, because the inner ear is located inside a special fluid, and as you probably already know, that it is more hard to move through a liquid than through a vacuum. The tympanic cavity focuses the pressure of sound waves so that they're strong enough to move the fluid in the inner ear. And it does this by the help of the auditory ossicles -- a trio of the smallest bones in your whole body : the malleus, incus, and stapes, commonly known as the hammer, anvil, and stirrup. One end of the malleus connects to the inner eardrum and moves back and forth when the drum vibrates. The other end is attached to the incus, which is also connected to the stapes. Together they form a kind of chain that conducts eardrum vibrations over to another membrane, the superior oval window, where they set those fluid in the inner ear into motion. Your inner ear is mysterious, complicated, and also interesting. It has some of the most complicated anatomy of your entire body, and don't worry, it is planted deep down in your head, so it's more or less, safe. It's other name : the labyrinth. It has two very important jobs to do : to turn those vibrations into electrical impulses that the brain can understand; and also help maintain your balance, or equilibrium, so that you are always aware which way is up or down and stuff. The labyrinth actually has two layers : the bony labyrinth, and the membranous labyrinth. The bony labyrinth is a big fluid-filled system of wavy wormholes. while the membranous labyrinth is a continuous series of sacs and ducts inside the bony labyrinth that basically follow the bony labyrinth's shape. Now the hearing function of the inner ear is housed in the cochlea, which has a back-of-a-snail-like structure. But the maintaining-your-equilibrium stuff is housed in the vestibular apparatus. Inside the vestibular apparatus, there is fluid that is controlled by the movement of your head. This structure has three semi-circles which all sit in the sagittal, frontal, and transverse planes. Based on the movement of the fluid inside of them, those three semicircular arches can detect movement of your head from vertically, horizontally, and in between those. So there you go. An essay on your ear, hearing, and how you can keep your balance, or equilibrium.

Monday, October 26, 2015

Lynx ( ESSAY )

A lynx, is any of the four species within the Lynx genus of medium-sized, short tailed, with tufts of black hair on the tip of their ears, a large and padded paws for walking on snow and long whiskers on their face. Under their neck, they have a ruff which has black bars resembling a bow tie although most times, this characteristic is not visible. Neither the caracal, sometimes called the desert lynx, nor the jungle cat, called the jungle lynx, is a member of the Lynx genus. Here are the scientific classification of the lynx that I have found :
  •  Kingdom: Animalia
  •  Phylum: Chordata
  •  Class: Mammalia
  •  Order: Carnivora
  •  Suborder: Feliformia
  •  Family: Felidae
  • Subfamily: Felinae
  • Genus: Lynx
There are four living species of the Lynx genus, the Eurasian Lynx, Canada Lynx, Iberian Lynx, and the Bobcat, and they are all believed to have been evolved from the Issoire Lynx that was believed to lived in Europe and Africa during the late Pliocene to the early Pleistocene. Out of the four living descendants of the Issoire Lynx, the Eurasian Lynx is the largest in size. They are native to the European and Siberian forests. The Eurasian Lynx is the third largest predator in Europe, next to the Brown Bear, and the Grey Wolf. It is a strict carnivore, consuming only about one to two kilograms of meat every day. The Canada Lynx or the Canadian Lynx, is a North American felid that ranges in forest and tundra regions across Canada and into Alaska. The Canada Lynx is also a good climber and swimmer. The Iberian Lynx is an endangered species native to the Iberian Peninsula in Southern Europe. It is the most endangered species of cat in the whole wide world. According to the Portuguese conservation group SOS Lynx, if the Iberian Lynx became extinct, it will be the first feline extinction since the Smilodon 10,000 years ago. The bobcat is a famous North American wild cat. With 12 recognized subspecies, it is common throughout Southern Canada, the continental United States, and northern Mexico.   

Taste & Smell ( ESSAY )

Now we are going to started diving into our "world of senses". How we experience our six major senses all boils down to one thing : "sensory cells translating chemical, electromagnetic, and mechanical stimuli into the "language" of our nervous system, which is action potentials". The process that changes chemical, electromagnetic, and mechanical stimuli into action potentials is called "transduction" and every organ of our body each have a different way to do it. Our vision functions with the help of photoreceptors, cells that detect light wave, while our senses of touch, hearing, and balance uses mechanoreceptors that detect sound waves and pressure on your skin. But our sense of taste or gustation, and smell or olfaction, works by sensing mechanical senses. They call on the help of chemoreceptors on our nose and mouth to interpret that stimuli into action potentials. The thought of our senses is just 5 or 6 are wrong. We actually have tons of secondary senses, like the ability to sense temperature, pain, acceleration, etc. That is all considered senses. Our most primitive and fundamental are our sense of taste and smell. Believe it or not, the sense of taste and smell are most strong at birth. As we get older, those two senses "decline", so the older we are, the less "good" our sense of smell and taste is. Tastes and smell are also powerful at activating memories, triggering emotions, and alerting us to danger. Now lets start to analyze how you can detect chemicals in the air and then turn them into the thoughts of "hmmm nice smelling pizza". All process starts as you and I sniff the molecules (or chemicals) of, lets say pizza. That means that the molecules are floating in the air, and that also means that the molecules are in a gaseous form, or volatile. And yes, when you smell poop, there is actually poop particles in your nose right there and then. Those pizza molecules that are floating in the air are vacuumed up your nose. Most of these is filtered out by your nose hair but not all of them. A few make it all the way to the back of the nose and hit your olfactory epithelium. This is your olfactory system's main organs. But here's the wonder of our sense of smell : Each olfactory neuron has receptors to detect a single kind of smell. At any given thing, like the pizza that you are smelling, there are hundreds of chemicals, like the thymol of the oregano, the butyric acid of the cheese, and much more. All the receptors that are "turned on" by the chemicals in the air, sends a signal to the brain, then the brain combined that all and tell you that, wow this is a very delicious smelling pizza. Scientist estimate that our 40 million different olfactory receptors neurons helps us identify about 10.000 different smell, maybe even more. Now just imagine a piano with thousands of keys able to produce millions of different combinations of sounds, you'll get an idea of how amazing our sense of smell are. So once the smell of pizza hit the olfactory neuron, it sends it to your brain through the olfactory tract to the olfactory cortex of the brain. From there, the pizza-smell hits the brain through two avenues : One brings the information to the frontal lobe, where they can be consciously identified, like oh, the smell of pizza; while the other pathway heads straight to your emotional ground control -- the hypothalamus, amygdala, and other parts of your limbic system. This emotional pathway is quick, intense, and fast to trigger memories. If the odor is associated to danger, like the smell of smoke, it quickly activates your sympathetic nervous system's "flight of fight" response. And these same intellectual and emotional apply to taste as well. Because taste is basically 80 percent smell. That's why when you couldn't smell, you usually also couldn't taste. As you chew your food, air is forced up your nasal passages, so your olfactory receptor cells are registering information at the same time your taste receptors are, so you are basically tasting and smelling at the same time. So, it's true when you caught a bad cold, or just hold your tongue so that air couldn't pass through your nose, you could still taste some food, but it would not be the same. So you can hold your nose and taste that something is sweet, but you could not pinpoint that it is caramelized sugar or just plain old sugar. Most of your taste buds are located on your tongue, but some is also located on your cheeks and other places on your mouth. As soon as you take a bite, all of the sensory information is quickly sorted by the ten thousand or so taste buds located on your tongue, mouth, and upper throat. Oh yeah, by the way, the taste maps of your tongue, that you probably have seen, are wrong. Those tongue diagrams date back to the early 1900s, when German scientist D.P Hanig tried to measure the sensitivity of different areas of your tongue for sweet, salty, sour, and bitter. The map that are resulted are pretty subjective, pretty much just reflecting on what his volunteers felt like they were sensing. While it's true that taste can be grouped into sweet, salty, bitter, and sour, all your taste buds, wherever they are can still taste all of those tastes. A little experiment. Try putting salt on the tip of your tongue, where the taste map tells us that that region is for tasting sweet, you would still taste the salt in all it's glorious saltiness.


P.S. : I mostly gathered the information to create this post from Crash Course. If you don't know 'em, check out their youtube channel, it's awesome, I'll promise you that. 

Thursday, October 22, 2015

Parasympathetic Nervous System ( ESSAY )

Consider your heart for a moment. For the average person at rest, like you probably are, sitting in front of your computer, reading from my blog, the heart beats at around 60 beats/minute. One beat per second. Nice and easy..... But if you were somehow be able to disconnect your heart from your autonomic nervous system, you will certainly guessed that things will change. But, your heart will not stop. Actually, it will be the opposite. Your heart rate will speed up. It will start to beat at around 100 beats/minute, 2/3 faster, and that is just at rest, without you breaking a single sweat. But your cardiac muscle would experience a lot of "wear and tear". The surrounding blood pressure would be under enormous pressure, and your body will suddenly require - and waste - a lot of energy. Basically your homeostasis - the name for when your body is in balance - would be ruined. Partly, the job of the parasympathetic nervous system is to keep your heart under homeostasis, or in balance. It's often described as the calming side, the mellow side of your autonomic nervous system, a kind of antidote to the effects of stress created by your sympathetic nervous system. But it's job is really much more than that. Unlike your sympathetic division, which deals with the "crisis of now", which is not a movie, by the way, the parasympathetic division deals with, well, everything else. It not only calms you down after being stressed out, but also it allows you to digest food, to reproduce, to excrete waste, to fight off infection, well everything other than becoming stressed, all the things you need to do to, well, be a living thing and live. But our bodies can only do that when they are in balance, somewhere between excitement and inhibition, both aroused enough but also calm enough, then your body can do the business of living. Our sympathetic and parasympathetic nervous system differ not only by their functions, but also by their positions and the positions of their ganglia. The sympathetic ganglia are located near the spinal cord, while the parasympathetic ganglia are found way out, or even in the effector organs. Likewise, the use of neurotransmitter in the two system are similar, but not exactly the same. In both system, the neurons release acetylcholine, in the preganglionic cell, which is the cell that comes before the ganglia. But the difference here is what comes after the acetylcholine crosses the ganglia. In the parasympathetic division, what comes out of the ganglia is still acetylcholine, while what comes out of the sympathetic division is norepinephrine. But, the biggest anatomical difference between these two system has to do with the physical networks that they form as they reach to every part of your body. The network of your sympathetic division -- I'm getting tired of spelling s-y-m-p-a-t-h-e-t-I-c and p-a-r-a-s-y-m-p-a-t-h-e-t-I-c all the time -- is found in the thoracolumbar area of your spinal cord. While the parasympathetic division are craniosacral, meaning they sprout from the bottom of your brain and just superior to your tailbone, and most of these nerves never go through your spinal cord.
Most of you will think that the two divisions of your autonomic nervous system as opposites or rivals, but that is a little off the mark. Looking at your body as a whole, you should picture them as two side of a scale. Sometimes your body tips a little to one side, and sometimes your body tips to the other side. The balance depends on having the right amount of both. The rate of action potentials travelling through your sympathetic division is known as your "sympathetic tone" and the tone travelling through your parasympathetic system is "parasympathetic tone". And most of the time, your parasympathetic tone is actually dominant, something I'm very glad to know.

Sympathetic Nervous System ( ESSAY )

So you're sound asleep, dreaming away, when suddenly the smoke alarm goes off. Before you even know it, you started to feel it, all the smoke and stuff. Those smoke alarms are loud - for a good reason. Your heart starts to race, your breathing picks up, you become sweaty all over your body. You are stressed. And I'm not talking about my-iPhone-is-about-to-die stress. I'm talking about maybe-I-am-going-to-die stress. Even though stress is often viewed as a dirty word, it, just like pain, isn't all bad, it's actually very useful if you're, y'know, trying to get off of a burning building and stuff. Your sympathetic nervous system is the part of your system responsible for stress, and it does it's job exceedingly well by focusing on what your body needs to do right now. Like if you are in a burning building. What you need to do is to run out of the building ASAP, not digesting the McDonald that you just eaten. That is stuff that you can deal later, when you are out of the life-threatening situation. So your sympathetic nervous system sweeps these suddenly trivial functions aside and focusing your blood and energy to the thing that needs to be done like, right now. So, pity on the guy that his sympathetic nervous system doesn't work well. But here is the problem: nowadays our bodies' stress responses are getting triggered all the time, even when you are not on a life-threatening situation, and that's not good. When you are stressed, you are basically overdriving your whole body, and that's a good thing if you are facing life-or-death ordeal. But if you are not, well, your body can get tired by being on overdrive for too long, and, well, "stressed". Like if you are late to an important meeting, but still stuck in a traffic jam, that kind of situation doesn't need your body being run on overdrive, but good luck explaining that to your nervous system. Because your physiological responses to non-immediate stress are largely the same as when you are fighting to stay alive. So that is why stress is sometimes - maybe most times, bad for you. Now I will tell about how your sympathetic nervous system takes over your body for several minutes. The stress signals includes two chemical : neurotransmitters and hormones. Neurotransmitters are made by and released by neurons themselves. While hormones are secreted by your glands. There are at least 50 different hormones in work in your body right now, and they do everything from regulating your sleep cycle, to making you retain water, so you don't get dehydrated. The understanding of neurotransmitters and hormones are 100% necessary for understanding how your sympathetic nervous system ultimately works. BUT! When you are trying to trace a single sympathetic signal, from the initial stimulus to the final response, that is a tough job, because the very same substances can have different effects, actually, sometimes, totally different effects depending solely on where it's being received in your body. And, fun fact, a compound can be considered both a hormone or a neurotransmitter without it changing a single bit, depending on where it is operating in your body. I know this is confusing, but bear with me. Ok, time to dive in. You are waken up by the smoke alarm. You need to move. Fast. Your brain sends action potentials down your spinal cord and preganglionic neuronal axons - I know, fancy words. Those signals flows all the way to their ganglia. When the signal reach the synapses inside the ganglia, the nerve fibers inside the ganglia then release a neurotransmitter, called acetylcholine, known to it's friend as ACh. In addition to working in sympathetic ganglia like this one, it's also what the rest of your peripheral nervous system and lots of your central nervous system uses to communicate. So when it comes to nervous communication, the ACh is basically the coin of the realm. The "Hermes" of your body. So the ACh crosses that synapse, and if there is enough of it, it can stimulate action potentials in several neurons at the other end. That's all it does. But it is important. It's basically a signal booster. Those actions potentials are then carried to the effector organs, in this case, let's say, your leg muscles, which are going to need an influx of blood if they are going to hustle you out of that house. And at the end of that second, the postganglionic neuron releases a different neurotransmitter. This one is called norepinephrine. It's what crosses that final synapse, and creates a response in the effector, like opening your blood vessel, so blood can flow more freely, providing your leg muscle the blood and oxygen it needed. So basically, the norepinephrine is the guy that "do" stuff, while the acetylcholine is, maybe kinda like the postman. Now the way the neurotransmitter/hormone like norepinephrine works, is a good example of another confusing aspect of your sympathetic nervous system. Because it works by both stimulating and inhibiting the same systems in your body at the same time. Like if you are in a life-or-death situation, norepinephrine your system releases causes an increase of blood flow in some parts of your body, and inhibiting blood to not flow to certain parts of your body where it's not needed right now, like to your stomach. That all depends on the organs. Several organs, like your stomach, have certain receptor that when triggered, will "prohibit" that organ. So it all depends also on what kind of receptor is getting triggered. Next, we will talk about the mellow-part of your autonomic nervous system, the one that tells you that it is now all right, the parasympathetic nervous system, so stay tuned.

Wednesday, October 21, 2015

Autonomic Nervous System ( ESSAY )

Your autonomic nervous system is the branch of your peripheral nervous system that regulates the functions of your internal organs, like your stomach, liver, and heart. It also controls your smooth and cardiac muscles, and your glands. All things that you do not consciously control, so yeah, you could say it has a lot of power over you. But thanks to it, you wouldn't need to command your brain to breath, to breath, the autonomic nervous system lifts that burden off of you. But the confusing thing about this system is that it's effect on your organs, muscle, and glands is by no means consistent. At any given moment, your autonomic nervous system is constantly making involuntary, fine-tuned adjustments to your body, based on the signals received by your central nervous system. This could mean changing your body temperature, or changing by what rate your heart is pumping blood. It's effects change, depending on the situation you're in, and also which part of your autonomic nervous system is in charge at that particular moment. Because this system that keeps you alive is actually run by TWO competing interests. Two divisions that serve the same organs, but they create different effects on them, one calming it down, while the other are making it more excited. The one that is dedicated to prepare you for activity, is the Sympathetic Nervous System, and the one that relaxes your organs is the Parasympathetic Nervous System. Together, they are what makes your body experience stress, fear, defiance, relaxation. So if there are an adventure novel, full of love, hatred, and tears that is being written in your body, it's probably being written by these two - the sympathetic nervous system and the parasympathetic nervous system.
Let's talk a sec about names. Contrary to it's comforting name, the sympathetic nervous system is what sounds your internal organs' alarm bells, therefore making your organs excited. It's the hardware behind the "fight or flight" response. Now the parasympathetic is for "resting and digesting", the opposite of the sympathetic system. It's responsible for conserving energy for later and maintaining your body. One more proof that you shouldn't judge or think about someone from their names or looks. Even though their basic components are basically the same, their physical structures are different in very important ways. Here are a list of those key differences which we'll be discussing later :
  • Relative lengths of their fibers
  • Location of their ganglia
  • Sites of origins of neurons from the central nervous system
And those three chief differences can help explain why they act like the foils that they are. Foils, by the way is like contrasts, contrasts of each other.

P.S. : I mostly gathered the information to create this post from Crash Course. If you don't know 'em, check out their youtube channel, it's awesome, I'll promise you that.
   

Thursday, October 15, 2015

Peripheral Nervous System ( ESSAY )

When it comes to the nervous system, or just your body in general, let's face it; the brain get's all the praise. And it deserves those praise. It's a complicated, amazing, and awesome piece of God's work. But the brain, even with all it's "amazingness", would be pretty useless without a support team that kept it connected to the outside world. Without a constant flood of external information that the brain can process, the brain starts to confuse it's own thoughts for actual experiences, and many other abnormalities. So it really needs that support team. And when talking about that support team, the peripheral nervous system is the one who came up for the job. Our peripheral nervous system keeps our brain in contact with the outside world and allowing it to respond to those information. This networks snakes to just about every part of our body. When you look at a human body "transparently", the peripheral nervous system is those tiny little "strings" that is everywhere and runs everywhere in your body. It provides the central nervous system with information, ranging from temperature, to the touch on your shoulder, or a twisted ankle. The sensory nerve receptors spy on the outside world for the central nervous system, and each type responds to different kinds of stimuli. They allow the central nervous system to communicate and feel the outside world. Here are a list of sensory nerve receptors that you and I have, and their functions :
  • Thermoreceptors : respond to changes in temperature
  • Photoreceptors : react to light
  • Chemoreceptors : pay attention to chemicals
  • Mechanoreceptors : respond to pressure, touch, and vibration.
We also have specialized nerve receptors called Nociceptors, that fire only to indicate pain. Most people go to great lengths to avoid pain, but pain is really an incredibly useful sensation, because it helps protect us from ourselves, and the outside world. It also help us to better protect ourselves from life-threatening situations. If you're feeling physical pain, it probably means that your body is under stress, damaged, or in danger, and your nervous system is sending a cease and desist signal, that tells you to back away from bonfires, or to not step on a needle, or to seek medical attention, like, RIGHT NOW!! Pain is a pretty subjective feeling, but the fact is, we all have the same pain threshold. That is the point where a stimulus is strong enough to reach a certain threshold. But you and I might have different tolerances for pain and discomfort. It's not our toughness that makes us more tolerance to pain, but the "tolerance" itself is the thing that makes you and I different in responding to pain. Just like my mom and dad. My dad can eat a plate of noodles, still putting of steam, and not burning his tongue in the process, but my mom can't. Instead, my mom has a higher tolerance rate in tasting cold stuff. My dad, say, can eat 10 scopes of ice cream before he get brain freeze, but my mom can eat 15 scopes of ice cream before getting the dreaded brain freeze. So the pain tolerance is different, but the pain threshold is the same in all of us. So in that way, pain is actually good for us, and that is why pain exists in the first place. Most doctors think of pain, as the perception of pain, whatever your brain is telling you what pain is. I'm not saying you should enjoy and try to be in pain until you can't no longer endure it....that would be stupid. All I'm saying is that you should realized that pain is one of God's many creative and brilliant ways to protect you, or you to protect yourselves.

P.S. : I mostly gathered the information to create this post from Crash Course. If you don't know 'em, check out their youtube channel, it's awesome, I'll promise you that.

Tuesday, October 13, 2015

Pistol Shrimp ( ESSAY )

Alpheidae, most commonly known as pistol shrimp or alpheid shrimp, is a family of caridean snapping shrimp, characterized by having asymmetrical claws, the biggest of them all can produce a loud snapping sound, which is either for scaring predator, killing prey, or to battle against their own species. Most snapping shrimp dig burrows, and are common inhabitants of coral reefs, submerged sea grass flats, and oyster reefs. Their family is diverse, and the population is distributed worldwide, consisting of about 600 species within 38 or more genera. Their scientific classification is:
  •  Kingdom: Animalia
  •  Phylum: Arthropoda
  •  Subphylum: Crustacea
  •  Class: Malacostraca
  •  Order: Decapoda
  •  Infraorder: Caridea
  •  Superfamily: Alpheoidea
  •  Family: Alpheidae
The snapping shrimp can grow to about 1-2 inches ( 3-5 cm long ). It is distinctive for the large claw, that can reach to more than half the length of it's already small body. The claw can be on either arm of the body. Unlike most shrimps, it lacks the pincers. But it do have a pistol-like feature made of two parts, one part can open up to about a 90 degree angle. Then to shoot, it slams the two parts together to create a enormous, powerful, super-hot bubble. Believe it or not, the bubble can reach temperatures up to about 4000 degrees C. That's almost as hot as the sun's temperature!!! The snapping shrimp also competes with the beluga whale and the sperm whale for title of the loudest animal in the sea. The pistol shrimp's "pistol" can reach up to 218 decibels. Think about it. An animal 1-2 inches long competing with an animal 18 feet long for having the loudest noise in the sea. That just blows my mind away.....

Central Nervous System ( ESSAY )

I hope you remember that our nervous system is divided into two main networks that work together to help you talk, think, and even move around : the central nervous system, which we'll be talking today, and the peripheral nervous system. The central nervous system consists of two main parts, the brain and the spinal cord. The central nervous system's main task is to :
  • integrate sensory information that the peripheral nervous system collects from all over our body
  • coordinating both conscious and unconscious activity
All of your sensations, thoughts, and directions are processed through this two-part system.
Our brain's job is to :
  • sorts out all sensory information
  • give orders
  • carries out our most complex functions like thinking, feeling, and remembering.
Meanwhile, the job of our spinal cord is to :
  • conducts two-way signals between your brain and the rest of your body
  • governing basic muscle reflexes and patterns
So, the spinal cord has some authority over something, other than just carry out signals from the brain to the rest of the body and from the rest of your body to the brain as I previously expected. Both our brain and spinal cord are made of fragile, jelly-like nervous tissue that is extremely susceptible to injuries. So all that "goo" is well-protected by the bones of your vertebrae and cranium, as well as membrane layers, or meninges, before being bathed in a cushy waterbed of clear cerebrospinal fluid. This fluid actually allows our brain to somewhat float in our skull, reducing it's weight in the process. But even with all that extra protection your skull and other "stuff" that protects your brain, it is still pretty vulnerable to injuries. That injury can come from outside of your body, or from inside, like in the case of some sort of virus attacking your brain. Your brain is divided into specialized regions, that may or may not interact with each other to produce a given action. So, let's say that a virus attack and damaged, say, the part of your brain that is in control of giving you the ability to understand and talk understandable language, then you will not be able to talk or understand anyone's speech, because the part of the brain controlling that is damaged. So you see that the brain is still pretty vulnerable, so we need to do our part to protect our brain and spinal cord. God has given us the protection necessary, like the skull, but we must also protect our brain and spinal cord the best we can.

P.S. : I mostly gathered the information to create this post from Crash Course. If you don't know 'em, check out their youtube channel, they are amazing.

Monday, October 12, 2015

Nervous System ( ESSAY )

The nervous system is the system that processed and executed all your thoughts, actions, and your particular way of making a sandwich. It received stimuli from your skin, your eyes, your taste buds on your tongue and processed them so you can feel that it is a thorn you are holding in your hand, that the building you see are grey and cool looking, and that the food you are eating are very bitter. The nervous system are like the headquarters of your body. And like most of the stuff that is in science, it too is divided into subgroups, the central and peripheral nervous system. The job of the nervous system as a whole is : Sensory Input, Integration, and Motor Output. Let's talk about an example to further understand this three main jobs of the nervous system. Let's say that you are sunbathing on your big backyard, when suddenly a spider walk on your foot. The feeling you feel of those eight, tiny, little legs is the first of the three main jobs the nervous system do for you, the sensory input part. From there, the nervous system process that information, and then decide what should be done about it. That's the integration part. So if you do anything that you are ashamed of when your friend joke you by putting a fake spider on your lunchbox, you should blame your nervous system about it. Then, maybe your leg just shoot of and kick that spider halfway across the country, then you are in the third part of the nervous system's job, the motor output. It's commands your muscles to do something. So whatever little thing you do, thank the nervous system for it, and, most importantly, thank the Creator of such ingenious system. Now let's talk about the separate parts of the nervous system. The central nervous system consists of your brain and spinal cord, the main control center. The peripheral nervous system is, well the rest of the group, which is composed of all the nerves that branch of from the brain and spinal cord to the rest of your body and it's job is to bring the orders from your brain and spinal cord to your muscles, to do the order. And since it's job is for communication, the peripheral nervous system is set up to work in both direction, sending information to your brain, and also to receive the orders sent back by the brain. So that's the organization of your nervous system in a nutshell. If you want to know more about the individual parts of the nervous system, check out my next post - if it has been posted yet.

P.S. : I mostly gathered the information to create this post from Crash Course. If you don't know 'em, check out their youtube channel, it's awesome, I'll promise you that.

Tissues ( ESSAY )

Our whole body are made of cells. About 7 octillion of them, to be precise. And every cells in your whole body, every single one of those 7 octillion cells, have a specific job, to keep the homeostasis going on in you body. Homeostasis, by the way, is a balance of materials and energy to keeps us alive. Back to the cell. Now every cell has a different job, but those jobs sometimes are very identical. Like, if a cells job is to "put garbage on garbage bin", and another cells job is to "pick up garbage from the ground", those job are very similar, and cells that have very similar jobs group together to form "tissues" that form a common function or goal to achieve homeostasis to keep you alive. FINALLY were in the part where we talk about the heading of this essay... Anyway, tissues themselves have different functions. Four different functions to be precise:
  • Nervous Tissue "Control and communication"
  • Muscle Tissue "Movement"
  • Epithelial Tissue "Cover and protect your body"
  • Connective Tissue "Provide support"
Nervous tissue control your communication and control. Nervous tissue forms the nervous system. Our nervous tissue has two big functions: to sense stimuli and to send electrical impulses through the body, often in response to the stimuli. This tissue are also made up of two different cell types: neuron and glial cells. Neurons are the specialized building blocks of the nervous system, they're what generates and conduct the electrochemical nerve impulses that let you think, dream, or do anything. They are also all over your body. When you touch a fuzzy dog, or a cold metal, or hot water, the neurons in your skin's nervous tissue send stimuli to your brain - not someone else's brain - that sense that stimuli and then you can feel the world around you, like fuzziness, coldness, or the unwelcoming feeling when you dip your hand in boiling water. No matter where they are, the neuron has a same anatomy, consisting of the cell body, dendrites, and the axon. The cell body, also called soma, is the "headquarters", containing a nucleus, mitochondria, and DNA. The dendrites, look like the root of the trees they're named after, and they're job is to collect the stimuli and information from other cells. They're the listening end. The long rope-like axon is the transmission cable - they carry messages to other neurons, and muscle, and glands, and stuff. The other type of nervous cell, the glial cells, are like the neurons pit crew, providing support, insulation, protection, and tethering the neuron cell to the blood vessels.
But your whole body would be utterly helpless if there are nothing or nobody that can do the commands the neurons send, which is why we have muscle tissues. Unlike our nervous tissue, the muscle tissue can contract and move. Muscle tissue also are well-vascularized, meaning it got a lot of blood coming and going, and it comes in three 'flavors', skeletal, cardiac, and smooth. Skeletal muscle tissue are found in our bone. This is the only one of the three that we can control. The other ones all work involuntarily, which is great, so we don't have to think to breath. The cardiac muscle tissue forms the walls of our heart, and works involuntarily. This tissue is only found in our heart. And finally we have the smooth muscle tissue, which lines the walls of most of your blood vessels and hollow organs.
Now we can finally talk about the epithelial tissue, which is the most awesomely named muscle tissue for me. The epithelial tissue is great at separating other cells from each other. It's like a burly gym teacher that knows what to do to keep his students in order. The epithelial tissue creates order where otherwise there would be total chaos and mayhem. Because we, humans, are filled with complex, fidgety, feisty systems that need to be separated to some extend if we want our different parts to achieve anything.
Now we will reach the most abundant and diverse of the four tissue type, the connective tissue. This is the stuff that keeps you -and me- looking young, makes up the skeleton, and delivers oxygen and nutrients throughout our body. It's what holds you, and me, together, in more ways than one. Connective tissue is pretty much every in our body, but the amount of how much is found in different parts of the body vary from organ to organ. For instance, the skin is made of mostly connective tissue, while the brain has very little, since it's almost all nervous tissue. There are four major classes of connective tissue: Proper, cartilage, bone, and most surprisingly, blood. Here are a list of what our connective tissue does to keep our homeostasis on play: Binding and supporting; protecting; insulating; storing reserve fluid and energy; transporting substances within our body; and also for movement. There is no other tissue that can boast of such high diversity as the connective tissue. But if there is so much diversity how can we group all these "diversityness" into one tissue group??? Well there are three factors that all the "branches" of the connective tissue have in common and the one that make them special : First, they share a common origin. They all form from mesenchyme, a loose and fluid type of embryonic tissue, which makes "vested" on them the ability to move oneself, which all other tissue type don't have. They also have different degrees of vascularity, or blood flow. Finally, and as strange as it may sound, all connective tissue are mostly composed of nonliving material called the extracellular matrix.

P.S. : I mostly gathered the information to create this post from Crash Course. If you don't know 'em, check out their youtube channel, they are amazing.

Thursday, September 25, 2014

Indonesia

Hai fellas. Cause I live in Indonesia I want to talk about Indonesia now. You won't call it respect if you leave your countries history behind, wound't you ? Now here is my interesting facts about Indonesia.

  • The country of Indonesia is ethnically diverse, with around 300 distinctive native ethnic groups and over 740 different languages and dialects spoken in the country.
  • Indonesia is the world's biggest muslim nation with over 88.2% of Indonesia's total population
  • Indonesia is the largest archipelago in the world with 17.508 islands, of which about 6.000 were inhabited
  • Indonesia has approximately 250 million people living in it ( 251.160.124 ) as of July 2013. 
  • Indonesia is the world's fourth most populous nation
  • Indonesia's largest city is Jakarta, also it's capital city, on the island of Java. It has a population of almost 14 million people making it the world's ninth largest city
  • The island of Java is home to 60% of Indonesia's total inhabitant ( around 130 million people ) making it the world's most populous island
  • The highest point in Indonesia is the peak of Puncak Jaya at the island of Papua sitting at 4.884 meters ( 16.024 ) above sea level  
  • The Borobudur Temple is the world's largest Buddhist temple and was earlier the Seven Wonders of the World
  • Indonesia is part of the 'Ring of Fire', the volcano group and about 75% of the total Ring of Fire volcanoes is in Indonesia
  • Indonesia is so expansive in its area covered that it has three time zones
  • Indonesia is home to thousands of flora and fauna, making it the country with second highest level of biodiversity in the world ( Brazil is #1 )
  • Indonesia is home to 12.7% of the world's Muslim population
  • Jakarta has the world's worst traffic jam known to man
  • Indonesia is the fourth most visited country in the world

Thursday, September 18, 2014

Thailand

Hello folks, now I want to tell about Thailand and some facts that may surprise you. Why  I choose Thailand ? Because 4 years ago I just make a trip to Bangkok, Thailand's capital city. And here is the interesting facts :
  • The official name of Thailand is the Kingdom of Thailand and it was formerly known as Siam until 1939 ( and again from 1945 - 1949 )
  • Thailand is the world's most populous country, with a population of 67 million people (67,448,120) as of July 2013
  • Thailand is the world's largest exporter of rice
  • Thailand's coastline is 3219 km long
  • Thailand has over 1430 islands
  • Doi Inthanon in the northern mountain range of Thanon Thong Cai is the highest point in Thailand at 2565 m (8415 ft) above sea level
  • Thailand is the 51st largest country in the world
  • Thailand is a constitutional monarchy, just like England
  • Bangkok once had dozens of canals & and its buildings stood on stilts earning the nickname Venice of the East. Most have now been filled.
  • Bangkok is the world's most visited city, according to the Global Destinations Cities Index, ahead of London
  • Bangkok's full ceremonial name is : Krungthepmahanakhon Amonrattanakosin Mahintharayutthaya Mahadilokphop Noppharatratchathaniburirom Udomratchaniwetmahasathan Amonphimanawatansathit Sakkathattiyawitsanukamprasit* while it's known to Thais as Krung Thep Maha Nakho*
  • Around 95% of Thai people are buddhist
  • The word "Thailand" means "land of the free"
  • The Garuda is the national and royal symbol of Thailand
  • Thai was voted the world's fifth friendliest country by Rough Guides readers
  • Thailand is home to the world's largest gold Buddha, the largest crocodile farm, the largest restaurant, the longest single-span suspension bridge, and the world's tallest hotel
  • Thailand has won 7 gold medal at the Olympic Games - three in weightlifting and four in boxing.
  • Thailand is the only country in south-east Asia that hasn't been colonised by Europeans
  • One-tenth of all animal species on earth live in Thailand
*= sorry if I spell any letter incorrect 

Thursday, August 28, 2014

Valentino Rossi

Hi guys, now I want to cover about the life Valentino Rossi, a famous MotoGp rider wearing number 46. If you are interested then read on....

 Valentino Rossi is born in February 16, 1979 in Urbino, Tavulia, Italy. When he was still a child his family move to Tavulia. Rossi love racing from he was still a little child. It came naturally from his father, Graziano Rossi, a former motorcycle racer. His mother, Stephania, did not want his son to race in motorcycle so young Rossi race in go-karts. 
 Just like his father, Rossi started racing in Grand Prix in 1996 for Aprilia in the 125cc category and won his first world title the following year. Then he moved to the 250cc still with Aprilia and won the 250cc World Title in 1999. He won the 500cc title with Honda in the last year of the 500cc, 2001. Then he won back-to-back titles in 2002 and 2003. In 2004 Rossi change bike from Honda to Yamaha and still win the 2004 title. He also win the 2005 season before regaining the crown in 2008 and again in 2009. He left Yamaha for Ducati in 2011 but go back to Yamaha for the 2013-2014 season.
 He not only love motorcycle but also love F1 and rally racing. He considered to became a F1 or rally rider after retiring from motorcycle.
 After 18 years -and counting- he gained this following stats:
  • 300 race starts
  • 106 Grand Prix victories
  • 186 podiums
  • 59 poles
  • 4879 points
  • 9 World Titles
He is considered by many the Greatest of All Time ( The GOAT ).     

Friday, August 22, 2014

Michael Jordan (MJ)

Hi guys. I really love basketball so I decided to write about several basketball legend. Below was one of the most spectacular of them all. Hope you all enjoy it.


 Michael Jordan was born in February 17, 1963 in Brooklyn, New York. He was the third of four children of James and Deloris Jordan. Michael as a young boy move to Wilmington, North Carolina. He goes to college in North Carolina University.
 Michael married Juanita in September 1989 and had 3 children: Marcus, Jasmine, and Jeffrey.
He then divorced and married Yvette Prieto and had a twin daughter named Victoria and Ysabel.
 MJ was selected third overall by the Chicago Bulls in 1984 NBA Draft. He first retired after a brilliant career for the first in 1993 after his father assasination in his hotel room. He then come back to NBA in March 18, 1995 with Chicago Bulls.
 He was considered as the best basketball player in history of basketball. He redifine basketball as a worldwide sport. He also boost Nike with his spectacular shoes, Air Jordan.

Wednesday, March 19, 2014

Dragonfly / Capung

Hi guys, pada kesempatan berikut ini aku akan membuat article tentang
capung. Binatang apakah yang paling sukses sebagai predator???? Orang-orang, termasuk saya sendiri tercengang ketika mengetahui bahwa predator paling ganas tak lain dan tak bukan adalah capung. Ingin mengetahui lebih banyak tentang hewan yang megalahkan singa dan hiu putih ini??? Baca terus article di bawah ini.
Capung atau sibar-sibar dan capung jarum adalah kelompok serangga yang tergolong ke dalam bangsa odonata. Mereka jarang berada jauh dari air, tempat mereka bertelur dan menghabiskan masa pra-dewasa anak-anaknya. Ini adalah klasifikasi ilmiah dari capung:

Kerajaan: Animalia
                                                         Filum: Arthropoda
                                                         Kelas: Insecta
                                                         Ordo: Odonata
                                                         Upaordo: Epiprocta
                                                         Infraordo: Anisoptera

Capung mudah dibedakan dari saudara nya capung jarum. Capung umumnya mempunyai tubuh lebih besar dan jika hinggap dengan sayap terbuka atau terbentang ke samping. Capung jarum umumnya bertubuh kecil, memiliki abdomen yang kurus ramping, dimana dia mendapatkan namanya, dan hinggap dengan sayap tertutup, tegak menyatu di atas punggungnya.
Capung dan capung jarum menyebar luas, di hutan, kebun, sawah, sungai, dan danau, hingga ke pekarangan rumah dan perkotaan. Beberapa jenisnya merupakan penerbang yang kuat dan luas wilayah jelajah nya. Ada juga yang mempunyai habitat yang spesifik dan wilayah jelajah yang sempit. Satu lagi perbedaan capung dan capung jarum, japung jarum biasanya terbang dengan  lemah, dan mereka jarang pergi jauh.
Siklus hidup capung, dari telur sampai mati, bervariasi dari 6 bulan hingga maksimal 6 atau 7 tahun. Capung menaruh telur mereka pada tumbuhan yang berada di air. Beberapa jenis lebih menyukai air yang tenang dan ada juga yang suka air yang agak deras. Setelah menetas, larva capung menjalani hidup di bawah air mengalami metamorphosis menjadi nimfa lalu akhir nya keluar dari air menjadi capung dewasa. Setelah dewasa capung hanya bisa hidup maksimal selama 4 bulan.
Capung merupakan sebuah mahluk purba. Mereka sudah ada di bumi sekitar 300 juta tahun yang lalu. Fosil terbesar yang pernah di temukan mempunyai ukuran lebar sayap lebih dari 3 meter.
Nah tentang hewan yang paling sukses sebagai predator, memang singa tercatat sebagai karnivora puncak pada rantai makanan. Tapi si raja hutan hanya mampu menangkap 25% dari total mangsa yang mereka kejar. Hiu putih sedikit lebih beruntung dengan 50% mangsa tertangkap. Tapi capung mempunyai persentase yang jauh lebih  hebat. Mereka mendapatkan 95% mangsa yang mereka kejar!!!! Hebat bukan??? Mungkin mereka kelihatan sangat bersahabat, tapi ternyata mereka sangat ganas dan hewan yang efisien dalam mengejar mangsa. Selera makan mereka pun sangat besar. Stacey Combes, seorang peneliti biomekanik di Harvard University yang mempelajari cara terbang capung pernah menyaksikan seekor capung percobaan di laboratorium menyantap 30 ekor alat buah secara berurutan. "Capung akan terus makan selama masih ada makanan" ujarnya.
Dengan mata majemuk nya, capung bisa memprediksi arah terbang mangsanya, termasuk sudut dan kecepatan, kemudian memperkirakan terbangnya sendiri untuk menangkap mangsa tersebut. Capung tahu kapan harus mempercepat, memperlambat, atau terbang menyimpang.
Teknik berburu milik capung berbeda dengan predator kebanyakan. Combes pertama mengira bahwa mereka mengejar mangsa secara aktif, begitulah cara singa memburu mangsa nya. Tapi ternyata mereka berburu dengan menyergap. Mereka datang dari arah yang tidak disadari oleh mangsa nya. Capung termasuk serangga terbang yang canggih. Mereka bisa melayang-layang di udara, menyelam di air, terbang mundur dan terbalik, dan juga bisa berputar 360 derajat dengan 3 kali kepakan sayap, dan mencapai kecepatan 30 mil per jam, luar biasa untuk seekor arthropoda.
 Sayap mereka juga berbeda dari serangga jenis lain. Capung memiliki empat pasang sayap transparan yang ultrafleksibel dan melekat pada toraks oleh otot-otot terpisah. Setiap sayap bisa bermanuver secara independen, memungkinkan capung melakukan berbagai manuver penerbangan. "Seekor capung dapat kehilangan seluruh sayap nya dan masih bisa menangkap mangsa." kata Combes.
Nah ternyata capung yang memiliki postur indah, bisa menjadi predator yang ganas. Nah sekian dulu penjelasan saya tentang capung, semoga bermanfaat.

Sumber: 

Wikipedia
Tempo.co

Tuesday, March 18, 2014

Kerajaan Indonesia dan Peninggalannya

Hi guys, beberapa hari ini aku sedang mempersiapkan diri untuk menghadapi UN. Nah pada kesempatan ini aku akan membahas tentang kerajaan yang berada di Indonesia sebelum hari bersejarah 17 Augustus 1945, dimana negara kita akhir nya merdeka dari para penjajah asing. Kerajaan tersebut ada yang bercorak Hindu, Buddha, dan Islam. Nah pertama aku akan membahas tentang KERAJAAN HINDU YANG PERNAH ADA DI INDONESIA:

Kerajaan Kutai
  • Berdiri pada tahun 400 Masehi
  • Berada di Muara Kaman, Kalimantan Timur di hulu sungai Mahakam
  • Kerajaan Hindu tertua di seluruh Nusantara
  • Raja pertama adalah Kudungga 
  • Peninggalan kerajaan Kutai adalah Yupa
  • Raja yang terkenal adalah Mulawarman 
  • Raja terakhir adalah Maharaja Dharma Setia
Kerajaan Tarumanegara 
  • Berdiri pada tahun 450 Masehi
  • Kerajaan Hindu tertua di Pulau Jawa
  • Terletak di Bogor, Jawa Barat
  • Raja yang terkenal bernama Purnawarman 
  • Peninggalan kerajaan Tarumanegara adalah 7 Prasasti 
  • Raja pertama adalah Rajadirajaguru Jaya Singawarman
  • Raja terakhir adalah Tarusbawa
Kerajaan Mataram 
  • Terletak di daerah Yogyakarta
  • Raja pertama adalah Raja Sanna
  • Peninggalan nya adalah Prasasti Canggal 
  • Wilayah kekuasaannya mencapai Pulau Jawa dan Bali
  • Raja yang terkenal adalah Balitung
Kerajaan Kediri
  • Terletak di tepi sungai Brantas, Jawa Timur
  • Raja yang terakhir adalah Kertajaya yang memerintah sampai tahun 1222 Masehi
  • Peninggalan berupa 9 Prasasti
  • Raja yang pertama adalah Jaya Warsa
  • Raja yang terkenal adalah Jaya Baya
Kerajaan Singasari 
  • Berdiri pada tahun 1222 Masehi
  • Raja pertama adalah Ken Arok 
  • Wilayah kekuasaan nya hampir meliputi seluruh Nusantara
  • Raja terakhir adalah Kertanegara (Joko Dolok)
  • Peninggalan kerajaan Singasari adalah Adalah 5 candi, 4 diantara nya sebagai makam raja
Kerajaan Majapahit
  • Berdiri pada tahun 1294 Masehi
  • Raja pertama adalah Raden Wijaya
  • Terletak di selatan sungai Brantas yang berpusat di Trowulan, Mojokerto
  • Disebut sebagai kerajaan Nusantara.
  • Kekuasaan nya meliputi Nusantara sampai ke Singapura dan Semananjung Melayu
  • Patih yang terkenal adalah Patih Gajah Mada
  • Peninggalan kerajaan Majapahit berupa 6 Candi 
  • Raja yang terkenal adalah Hayam Wuruk
  • Raja yang terakhir adalah Brawijaya (Kertabumi)
Kerajaan Pajajaran
  • Berdiri pada tahun 1333
  • Berada di Priangan, Jawa Barat
  • Raja yang terkenal adalah Sri Baduga Maharaja
  • Raja yang terakhir adalah Prabu Sedah
KERAJAAN BUDDHA DI INDONESIA:

Kerajaan Kaling/Holing
  • Berada di Jepara, Jawa Tengah
  • Diperintah oleh Ratu Simo (Sima)
  • Peninggalan kerajaan Kaling berupa prasasti 
Kerajaan Sriwijaya
  • Berdiri pada abad ke-7
  • Raja pertama Sri Jayanegara
  • Berpusat di Palembang, Sumatera Selatan (Muara Sungai Musi)
  • Wilayah Sriwijaya meliputi Sumatera, Kalimantan Barat, dan Semenanjung Melayu
  • Disebut Kerajaan Nusantara pertama
  • Dikenal sebagai kerajaan maritim
  • Pusat pendidikan penyebaran agama Buddha
  • Pusat perdagangan, karena Palembang merupakan jalur perdagangan nasional dan internasional
  • Bangunan peninggalan kerajaan Sriwijaya adalah Candi Muara Takus dan bangunan tempat suci Biara Bakal
  • Peninggalan prasasti ada 5
  • Raja yang terkenal adalah Bala Putra Dewa
KERAJAAN ISLAM DI INDONESIA

Kerajaan Samudera Pasai
  • Terletak di Lhokseumawe, Aceh
  • Berdiri pada abad ke-13
  • Merupakan kerajaan Islam pertama di Indonesia
  • Raja pertama bernama Marah Silu yang bergelar Sultan Malik Al-Saleh
  • Peninggalannya adalah mata uang emas dan makam Raja Malik Al-Saleh di Gedong, Aceh Utara
Kerajaan Aceh
  • Berdiri pada abad ke-16
  • Raja pertama Sultan Ali Mughayat Syah
  • Berada di tepi Selat Malaka yang berpusat di Kutaraja, Banda Aceh 
  • Raja yang terkenal adalah Sultan Iskandar Muda
Kerajaan Demak
  • Berdiri pada abad ke-16
  • Berdiri pada tahun 1513
  • Merupakan kerajaan Islam pertama di Pulau Jawa
  • Terletak di muara sungai Bintoro, Demak, Jawa Tengah
  • Raja pertama Raden Patah
  • Julukan Adipati Unus adalah Pangeran Sabrang Lor
  • Peninggalan Kerajaan Demak salah satu nya adalah Masjid Agung Demak
  • Raja yang terakhir adalah Sultan Trenggono
Kerajaan Pajang
  • Berdiri tahun 1568
  • Berada di Surakarta
  • Raja yang pertama adalah Sultan Hadiwijoyo 
  • Raja yang terakhir adalah Ario Pangiri
Kerajaan Banten dan Cirebon
  • Didirikan oleh Sunan Gunung Jati, Panglima Kesultanan Demak 
  • Mengganti nama Sunda Kelapa menjadi Jayakarta (Jakarta) pada tanggal 22 Juni 1527
  • Peninggalannya antara lain adalah Masjid Agung Banten
  • Raja Banten yang pertama adalah Hasanuddin
  • Raja Banten yang terkenal adalah Sultan Ageng
  • Raja Banten yang terakhir adalah Panembahan Yusuf
Kerajaan Ternate dan Tidore
  • Terletak di Sampalu, Ternate dan Pulau Tidore di Maluku Utara
  • Berdiri pada abad ke-16
  • Raja pertama adalah Sultan Zainal Abidin
  • Raja terkenal adalah Sultan Hairun dan Sultan Baabullah
  • Hasil utama adalah cengkih dan pala
Kerajaan Gowa-Tallo
  • Berada di Somba Opu, Makassar, Sulawesi Selatan 
  • Raja terkenal adalah Hasanudin 
  • Sultan Alaudin dari Gowa dan Sultan Abdullah Awalul Islam dari Tallo menggabungkan kedua kerajaan menjadi dwitunggal
  • Salah satu peninggalannya adalah Rumah raja Gowa 
Nah cukup sampai di sini dulu. Mungkin masih banyak banget kerajaan yang tidak di catat, jika ingin mengetahui lebih banyak bisa melihat di Google.com.

Bye guys, I will see you all at my next post, hope it didn't take long.

SUMBER:

  • http://www.invir.com/kerajaan.html
  • http://www.wikipedia.org


Wednesday, August 28, 2013

Wildebeest

The ungainly gnu earned the Afrikaans name wildebeest, or ''wild beast," for the menacing appearance presented by it's large head, shaggy mane, pointed beard, and sharp curved horns. In fact, the wildebeest is better described as a reliable source of food for the truly menacing predators of the African savanna: lions, cheetahs, wild dogs, and hyenas.
Here's a fast fact about this magnificent animal:

                                                           Type: Mammal
                                                           Diet: herbivore
           Average life span in the wild: 20 years
           Size: up to 4.5 ft (1.4 m)
           Weight: 330-550 lbs (150-250 kg)
           Group name: herd
           Size relative to a 6-ft man (2 m) man:

 The gnu (pronounced "g-new" or simply "new") is a member of the antelope family, although it's heavy build and disproportionately large forequarters make it look more bovine. Gnus can reach 8 feet (2.4 m) in length, stand 4.5 feet (1.4 m) tall at the shoulders and weight up to 600 pounds (272 kilograms). Both male and female wildebeest grow horns.

 Their habitat comprises the grassy plains and open woodlands of central, southern, and eastern Africa, particularly the Serengeti in Tanzania and Kenya. They travel in large herds and are active day and night, grazing constantly. Pretty cool, eh?


Their spectacular northward migration in search for greener pastures is dictated by weather patterns, but usually takes place in May or June. It is considered one of the greatest wildlife spectacles on earth, involving up to 1.5 million wildebeest as well as hundreds of thousands of other animals, including zebras and gazelle.

 Up to 500.000 calves are born in February and March each year, at the beginning of the rainy season. Calves learn to walk within minutes of birth and within days are able to keep up with the herd. Gnus can live to be 20 years old. That's all for today folks, hope you enjoy reading my blog. GBU you all.

Monday, July 29, 2013

Our Earth.

Hi, and welcome to my posts about our earth. Several years ago I  learn about our amazing, beautiful world. And I am gonna tell you guys about what I learn. Our home is a wonderful world created by God for us to live in it. Let's first learn about the outer appearance of our earth. Way out there in outer space our earth looks like a large sphere (ball). It has vast swarms of white clouds, blue oceans and green land area. At the top of our earth is the North Pole while at the bottom lies the South Pole. Both the poles are covered with ice caps that appeared white. Our earth viewed from space is truly beautiful.
Let's consider about some details about the overall structure of the earth.
                   Size and Shape.
Our earth is shaped like a sphere. However.... our earth is not completely round. It is slightly flattened at the poles. This means that the diameter of the earth measured from the North Pole to the South Pole is slightly less then the diameter across the middle of the earth, at the equator. From pole to pole the diameter of the earth is about 7,900 miles ( 12,714 kilometers ). At the equator, the diameter of the earth is about 7,926 miles ( 12,756 kilometers ). Therefore, the distance from pole to pole is 26 miles ( 42 kilometers ) less than the diameter of the earth at the equator. That's why it's slightly flattened at the poles although it may look perfectly round from far away in space. In the same way the distance around the earth is shorter at the poles than at the equator. At the poles, the earth is 24,860 miles ( 40,008 kilometers ) around. At the equator, it is slightly greater : 24,902 miles ( 40,075 kilometers ) around. However, the equator is not actually the "fattest" part of the earth. The distance around the earth is greatest along a circle slightly south of the equator. Therefore, the earth's shape is a little like a pear, which had it's fattest just bellow it's middle. But this bulge in the earth's shape is so small that the earth still looks like a perfectly round sphere when viewed from space.                                                                            
                                                                             Layers of The Earth
You might think of layers as layers of a cake, but that isn't what I meant. The earth really does have layers, like a cake. The layers name are, from the top to the bottom, Crust, Mantle, Outer Core, Inner Core.
CRUST : The crust is the outer layers of our beautiful earth. It contains all life on earth because life isn't sustainable below the crust.
MANTLE : The mantle is the thickest part of all the layers of the earth. The mantle is made up of two parts. The upper part is name asthenosphere and is 200 km ( 200 mi ) thick, and the lower part is name lithosphere composed of rigid rock about 50 - 120 km ( 31 -  75 mi ) thick.
OUTER CORE : Our earth's outer core is made up of liquid layer about 2.266 km ( 1.408 mi ) thick. It is made of nickel and iron. The temperature of the outer core is estimated about 4.300 K ( 4.030 C; 7.280 F ).
INNER CORE : The earth's inner core is the hottest, innermost part of our earth. It is primarily a solid rock with a radius about 1.220 km ( 760 mi ) according to seismological studies. It is believed to be on an iron-nickel alloy and to be approximately about the same temperature as the surface of the sun : approximately 5.700 K ( 5.430 C ).